Controller for electric motors.



0. F. SHEPARD, JR. CONTROLLER FOB ELECTRIC MOTORS. I APPLIMTION FILED JAN. 15, 1906. 936,952 Patented Oct. 12,1909.

3 SHEETS-SHEET 1.

35131215525 v Q Invah Fur".

O. F. SHEPARD, JR. CONTROLLER FOR ELECTRIC MOTORS.

APPLICATION FILED J4n. 1s, 190s.

Patented 0bn.-12,1909.

3 SHEETBSHEBT 2.

. 0. F. sHEPARmJR. CONTROLLER FOR ELECTRIC MOTORS.

' APPLIOATION PILED JAN. 15, 1 906,.

Patented 0t.1 2 ,1909.

3 SHEETS-SHEET 3.

I I l I I A 1 I I UNITED STATE-S PATENT OFFICE. i

OSCAR F. SHEPARD, J 3., OF CINCINNATI, OHIO, ASSIGNOR TO THE WARNER ELEVATOR 1 MANUFACTURING COMPANY, OF CINCINNATI, OHIO, A CORPORATION OF- OHIO.

CONTROLLER FOR ELECTRIC MOTORS.

Specification of Letters Patent. Patented Oct, 12, 1909,

Application flled January 15, 1906'. Serial No. 296,191.

which the following is a specification.

' for etfectin This invention relates to certain improvements in controllers and more particularly in controllers of the magnetic 'rheostat type, -and the ob3ect ot-the invention is to provide a device of this character of a comparatively simple and inexpensive nature which shall be adapted for employment not only for, the variation of the starting resistance but shall also be capable of operation for effecting a variation of resistancein the shunt field circuit, whereby the improved controller is especiall with siunt and compound-wound motors v speed variations during the operation of the motors.

The inventionconsists, inpart, in a controller of this general character wherein the ma netic elementsare adapted for inclusion. in t it": shunt field windings of the motor, so as to form, essentially, parts or sections of the shunt field resistance, whereby, in the practical;employment of the improved controller, an important economy In the consuinptioniof energy is attained. t

The invention further consists in the em.- ployment, in the improved controller, of means actuated from each of the respective magnetic elements and controlling the circuit connections of the succeeding magnetic elemcl'its, whereby the operation of the 1m proved controller in effecting the several resistance variations isrendered substantially" automatic in character.

T he invention also contemplates. certain novel features of the'construction and-conibinations and arrangeli ents of the several afforded against damage due to carelessness and inexperience on the part of the operator, as will be hereinafter fully set forth.

The novel features of the invention wil-lbe carefully defined intheclaims,

In the accompanying drawings which adapted for service in connection serve to illustrate my invention-Figure 1 is a'diagraphic view showing-a controller embodying my improvements, the several parts being shown in the positions wherein they stand when the motor is at rest; Fig. 2 is a diagraphic view somewhat similar to Fig. 1, but showing the positions assumed by the parts of the improved con troller when actuated to cut out the starting resistance, a modified arrangement of the means for preventing damage due to too sudden reversal of the motor being also illustrated in this view; Fig. 3 is a view similar to Fig. 2, but showing the positions assumed by the parts of the improved controller when actuated to augment the shunt field resistance of the motor for increasing the running speed thereof; F ig. t is a detail view showing in elevation,

detached and on an enlarged scale, the

means, illustrated in Figs. 2 and 3, for safeguardin against too sudden reversal of the motor; h ig. 5 is .a View similar to Fig. 4,, but illustrating the alternative safeguardin means' shown in Fig. 1; Fig. 6 is a sectiona view taken axially through one of the mag netic elements of the improved controller and illustrating certain features of the means for retarding theoperation thereof; Fig. 7 is an enlarged sectional detail view showing the arrangement of the valved air vent forming part of the retarding means illustrated in'Fig. 6, and Fig. 8 is a partial plan View showing the construction of the valve controlling the vent of said retarding means. Fig. 9 is a detached detail view showing the mam-switch shaft in cross-section for illustration of the compensating or loose connection between said main-switch shaft and the shaft of the reversing-switch.

In these views 1 indicates a switch-board whereon is mounted a main switch comprisinga shaft 6 mounted to rock between upper and lower rows or series of contacts and carrying switch elements 7 and 8 insulated from each other and adapted, respectively, when the shaft is rocked, tomake simultaneous connection with certain contacts of the upper or lower series. The arrangement of contacts in the upper and lower-series is simi; lar and corresponding contacts in the respective series. are electrically connected sothat similar connections are afforded by theeleinents 7 and 8 no matter-in whichdirection .shaft- 6 is rocked,'it being understood, how:

ever, that when the shaft is roclredto' bring its elements 7 and 8 to a position central between the upper and lower series of contacts,

'electrical communication of said elements groups or series of the main switch and.

ada )ted, when the shaft 6 is rocked in either direction from its central position, to be engaged by the respective switch elements 7 and 8, whereby communication is established from the terminal 2 to the element 7 and from the element 8 to the terminal rent fiows trom Adjacent to the,contacts 4; for the feed terminal 2, the upper and lower series or rows on the switch-board l comprise other contacts 9, adapted, when the shaft 6 -is rocked, to be engaged by the switch element 7, whereby electrical communication is established across the element T between the contacts 1 and 9 and the contacts 9 have connection with a conductor 10 leading to one arm or element 11 of a reversing switch having a shaft 12 and adapted for operation in unison with the main switch shaft 6 so that said armor element 11 is adapted for mak- I ing electrical connection with either of two contacts 13 or 14 it being understood that when the shaft 12 is rocked in one direction, said arm 11 communicates with the contact piece 13 and when said shaft is reversely rocked, said arm 11 communicates with the other contact 14%. I

15 is. a conductor extended from the reversing contact 13 to the motor 22 where-it has communication with the windings or the armature 16 of the motor and 17 is a return conductor extended from the opposite armature terminal of the motor to the reversing contact 14*.

1 11 another arm or element on shaft 12 of the reversing switch and insulated from arm 11 and adapted, when said shaft is rocked, to communicate with one or the other of two contacts 13 and 14 simultaneously as the arm 11 communicates with one or the other of the respective contacts 13 or 141. The contact 13 has electrical connection with the conductor 17, so that when the reversing switch is actuated to establish communication of arms 11' and 11 with the respective upper contacts 13 and 13, the curthe feed terminal 2 by way of contact 4;, switch element 7, contact 9, conductor 10, switch arm 11, contact 13 and thence by way of conductor 15 to and through the miniature windings of themotor 22, whence it fiowsby the return conductor 17 to contact 13? and switch arm 11 The reversing contact 14 of the switch arm 11 is in communication with the conductor 15 and whenthe shaft 12 is reversely rocked from the position shown in Figs. 2 and 3,,

communication is established between the arms 11 and 11 and their respective lower contacts 14. and 14, so that the current fiow from the switch arm 11 through the armature 16 of the motor 22 is reversed, such flow being then from arm 11 to contact 14 and thence by conductor 17 to and through the windings of armature 1(3, whence it returns 1 by conductor 15 to contact 1 1 and switch arm 11".

From the switch arm 11" of the reversing switch are extended conductors 18 and 20,

leading to the series fieldwindings 21 of the motor 22 and from the opposite terminal of said series field windings is extended a conductor 23 leading to the starting resistance, comprising sections 24,25 and '26, whence extends a conductor 27 leading to main switch contacts 28 on the switchboard 1 opposite tothe contacts 5 thereon and adapted,

when the shaft 6 is operated, to communicate therewith and with the feed terminal 3 through the switch element 8.

, 29 represents-a loose or compensating connection between the main switch shaft 6 and the shaft 12 of the reversing switch so that the said reversing switch shaft 12 is operated and rocked in unison with the movement of the main switch shaft 6, but to a' lessened extent, whereby the reversing switch shaft 12 is permitted to lag behind the main and 5. By reason of this compensating or loose connection 29, when the main shaft 6 is operated to move 1t to a central position .switch shaft 6 to an extent such that the a wherein its elements 7 and 8 are out of com munication with their respective contacts,

the arms 11 and 11 of the reversing switch will remain in communication with those contacts 13 and 13* or 1 1 and 14 with which 7 they were previously engaged and such'coni: munication of the reversing switch arms and contacts will not be interrupted until the main shaft (3 shall have been rocked past its central position to bring its elements 7 and 8 ,into communication with those main switch contacts opposite to the main switch contacts with which communication was previously established. As shown in Fig. 9, this compensating or loose connection 29 comprises adapted, when said main-shaft is rotated,

a pin or projection 29 onmain-shaft 6 and for a certain extent of free movement or" play between shoulders 29",29 within' a collar 29 on the reversing-switch shaft 12.

The" detailed construction of the loose or compensating connection 29is unimportant and the purpose of the arrangement and operation above described will be hereinafter explained.

' For rocking the main switch shaft (3 I gravity and move the shaft 6 to a central position with its elements 7 and 8 central between and out of colnnnnncation with both the upper and lower series of contacts 4, 9, 28 and 5, and when one of sald'solenoids as, for example, the solenoid 31, is energized, its core 32 will beuplifted, asshown in Figs. 2 and 3, whereby the main shaft 6 2 will be rocked torits fullest extent inone direction so that, as shown in Figs. 2 and 3,

. the elements 7 and 8 of the main switch will be brought into communicationwith ithe i1 per serles of contacts 4, 9, 28 and 5 A30 and t e arms 11 and 11 of the reversing switch will likewise be brought into comf munication with the up er contacts 13 and 13. Should the soleno1d'31 be energized instead of the solenoid 31, it is evident that a reverse rocking movement of shaft 6 would be-efl'ected, resultin in a reversal of the communications of the switch elements and arms 7, 8-, 11 and 1.1. r

Forv controllin the operation of the y swi'tch actuating evice 30, I preferably pro vide a pilot switch suchas is shown at 42, and which is also adapted for controlling tl1e ofiieration of'flcertain other mechanisms v 'a-s'wi Ib'e' hereinafter explained. The wind- 'ings'of the solenoids 31 and 31* have com-- connection. with a conductor 34 leading I nvthemain switch contacts 4 where it has-connection with the feed terminal 2 for thejsupplyof energy for o )erating the actu- 59 ating mechanism-30. Sai conductor 31 ineludes two se arated terminals or contacts 3'5,a1id-38 which are adapted to be bridged over and electrically connected when the parts are at rest, as seen in Fig. 1, by a -carbon block or contact piece 36 forming part of an auxiliary controlling switch "which is adapted 'for automatic operation,

' as will be hereinafter explained, for controlling the supply of energy to the switch 0 actua tixlg mechanism 30 from the feed termi- The' windings of' the respective solenoids 31 and 31"hav e independent connection'by way of-conductor. AOandAO, respectively 5 with sirnil'ar but" -ns'ulated contaet's 41' and -11 of the pilot switch 42, said contacts 41' and 41 being at opposite sides of the central position of a switch lever -13 so that, when said lever is moved in one direction, it will communicate with one of said contacts, as for example, the contact -11 as theparts are seen in Figs-.2 and 3,to energize the solenoid 31 and rock the switchshaft (i in one direction, or when said lever Al'is reversely moved and con'imunicates with contact 41.", communication will be established through conductor 10 with solenoid 3'1 which will thereupon be. energized to r'eversely rockthe main switch shaft 6.

14 and 4% are other contacts above the contacts +11 andx tl and also, at opposite sides of lei'er 43 when centrally positioned so that when said lever is moved to communicate with one or the other of the con-1 tacts 41 and -il 'it will also communicate with the corresponding cont-act 44-01 44*. Contacts 44 and 44* have common connectacts 5 of the main switch and communicating through thesame with the feed terminal 3,'so that when lever513 is moved in one direction, as toward theiright to the position 'shown in Fig. 2, whereby communication is fl'tion with a conductor 45 leading to the con- I verse ly moved, the current traverses a similar path except that the circuit connections I of solenoid 3.1 are substituted for the par allel connections of solenoid 31 in order that versely move the mam switch shaftfi.

The shunt field circuit includes a conductor 53 in communication withfe'ed con-. ductor 2through conductor 10, contacts 9' and 4 and switch element 7 and leading to the solenoid 31 may be energized-to re.-'

theshunt field coils '54 of the 1notor22,

whence isextended a conductor 55 which includes the' term nal contacts and circuit switch 37 (see Fig. 1) b means of which the supply of energy. for the operation of theswitch actuating mechanism 30-is coa trolled as above set forth. 'The partial eircuit 82 has connection with the conductor 27 leadmg {from the series field windings to the contacts2'S of the main switch and communieatingfthropgh switch element 8 with 115. closing parts or connectors'of a 'plurality I the contacts 5 of the feed terminal 3, so that when the circuit'is closed at the main switch, the current will flow from feed terminal 2 a by way of contacts 4, switch element'7, contacts 9, conductors 10 and 53 to and through the shunt field coils 5% at the motor, returning by way of conductor (including the lowered connectors of the several circuit breaking devices) partial circuit 8:2, "conductor 27, contacts 28, switch element 8 and contacts 5 to feed terminal 3.

As shown in the drawings, the improved controller is provided with eight magnetic rheostat elements, each of which comprises a solenoid 62 having a movable core provided with a pendent stud (33 at its lower end whereon are carried certain circuit making and breaking devices as will be hereinafter explained. These eight rheostat elements are divided into upper and lower grou s of four elements each, the u per group 0 elements 37, 59, and 61, eing adapted for successive o eration tocontrol the starting resistance w ich may be said to include the three starting resistance sections 26, 25 and 24, together with the series field windiiws 04 of the motor, while the lower group 0' elements 49, 50, '51 and 52 are adapted for successive operation to control the insertion of four resistance sections 429 50 51 and 52 in the shunt field circuit of the motor for varying the running speed of the motor after It will, however, be apparent that rou'ping of the magnetic starting. the number and rhcostat elements in the improved controller is immaterial to the presentinvention and may be varied at will to conform'to various modifications andarrangements of the resistancesections whlch may be found desirable in practice. For example, either the starting" resistance "sections, together with the magnetic elements for their control, may be. in greater or less number, or may even be omitted altogether, the series field windings,

in some motors serving to afiord suliicient resistance for starting, or said series windings ma'y be divided in sections each con trolled by a magnetic element or said windings, together with the magnetic element for their controlmay be dispensed with as in the case of a simple shunt wound motor. Or, ifdesired, the shunt resistance sections, together with the magnetic elements controlling their insertion may be dispensed with without departure from the' principles 1 of the invention.

is prevented, and the preferred construction of said magnetic elements is illustrated in the solenoid (3:? are shown applied upon a brass tube 64, the bore of which is arranged to snugly receive the core ()6 so that undue escape of air between the parts is prevented when the core is moved vertically in said tube. tube is also 0 osed by a plug or capha v' inga conical lower end depending withln the upper end of said bore, and the u per end of said core (36 has a central conic, recess 67, and'carries a acking or buffer 68 in annular form and a apted,by engagement on the conical lower end of the plug or cap 65, to receive the impact of said core when the same is elevated at the energization of the' solenoid.

. 69. is an air duct produced in the cap or plug 65 and adapted for the escape of air from the bore of tube 64 when the core 66 is elevated therein, the upper end of said duct being counter-bored as seen at Fig. 7 to receive a screw valve 70, one side of which is slightly out or filed away to produce an outi let as seen at 71 for the discharge of air es caping by way of the duct 69. The enlarged or counterbored upper end of the duct 69 wherein the screw valve 70 is received affordsa valve seat surrounding the duct and the lower end of said screw valve is tapered,

'to produce a valve surface whicln'when the screw is-turned, is adapted to be moved toward or away from said valve seat to in crease or diminish the capacity of the duct for the'discharge of air. 7

Since the air is prevented from escaping between the core (SS-and tube 6% when said core is elevated at the energization of the solenoid, it follows that said air being imprisoned in said tube forms an elastic cush-- ion by 'means of which'the elevation of the core is retarded in a well known way, and the screw valveTO being properly adynsted,

The ulpper'end of the bore of said the escape of air atthe duct 69 is very gradual so that a suiiicient interval of time is afforded 1n the operation of the magnetlc rheostat element to prevent damage to the parts from operation of the elements in too 'apid succession.- But when the solenoid is I deenergized it is desirable to permit its core to fall quickly by gravitation and since the construction above described would serve to retard the descent of the 'coreas well as its elevation, I provide the core 66 with an axial duct 72 counterbored at its u pperlend-where it communicates with theeentral conical recess '67 at the upper end of the core. .By means of said counter-bore a valve seat 1s produced surrounding the duct 72 and said seat is normally engaged by a ball VtllW-l 73in the counterboreinnd serving to prevent escape of air by Wayne" ,duct 7 2 when the core 'is moved upward, while, when the solenoid is deener'gized, air is permittedto freely pass the valve 73and enterthe-bore of tube 64511;!)

cperinitthecore 66 to drop quickly by gravitation so that the elements may be returned to their positions of rest in a substantially instantaneous manner when the controller is operated to open one or another of the motor circuits.

Eachmagnetic element 37, 59,60 and 61 of the upper group comprises a circuit closing device formed of a laminated-copper brush T5 carried by the stem 63 of its solenoid core and normally, when the parts are at rest as shown in Figs, 1 and 5,. said brush is out of contact with superposed contact points 76 and 77 which are included, respectively, in

partial circuits 78, 7 8, having series connection with each other as seen at 79, the part al circuits 78, wherein are lncluded the contacts 76 and 77 of the circuit closing devices of the first three magnetic elements 37, 59 and 60 of said upper group being, respectively, connected by conductors 80 in parallel with the several resistance sections 26, 25 and 24 of the starting resistance, while the fourth partial circuit 7 8, which includes the contacts 76 and 77 of the circuit closin device of element 61, has connection, as s iown at 81. with the conductor 18 of the series field circuit and consequently is in parallel connection with the series field windings of the motor. By this arrangement itwill be evident thatwhen the elements 37, 59, 60 and 61 of the upper group are operated and their solenoids 62 are energized to elevate their cores, the respective partial circuits 78, each of which is normall 0 on between the contacts 76 and 77 wil e completed by the movement of the brushes 75 on the stems 63 into engagement with said contacts, whereby in the successive operation of the. several magnetic elements, the starting resistance sections 26, 25 and 24 will first be successively short-circuited and afterward, by the operation of the last element 761 of the'group,

the series field windings 21 which constitute,

essentially, the final section of. the starting resistance, will also be short circuited.

Each of the, magnetic rheostat elements in both the upper and lower groups comprises a circuit breaking device formed of a carbon contact brush or connector 57 and contact pointsor terminals 56 and 58, between which COHHIIHXHCQUOIL 1S established by said brushor .connector when in its normal lowered position of rest as shown in Fig. 1. Each brush or block 57 is carried loosely on the pendent stem 63 of the core of the corresponding solenoid 62, being insulated from such stem, however, and said stem is adapted for a certain extent of vertical movement independent. of the brush or connector 57,. so that when the solenoid 1s denergizcd and its core falls by gravitation, the brush or connector will engage and'rest upon ts contacts 56 and 58 to establish communication between said, contacts before the stem 63 of the,

solenoid shall have reached its lowermost position, Qonversely, when the solenoid is energ zed, its core and stem 63 areelevated to a certaiueiitent before the connector or a brush 57 is raised to break communication between contacts 56 and 58. This result is attained by perforating the connector 57 for I As above set forthl the circuit breaking devices of the several magnetic elements 37,

59, 60, 49, 50,51 and 52 have their contacts 56 and 58 included in the c the shunt field circuit, so tha in the normal the solenoids of t e" magnetic elements have operated, the on rent in the shunt field circuit traverses each of the connectors 57 which, being then in lowered position, afi'ord communication between their respective contacts 56 and 58.

82, 83, 84 and 85 indicate four partial ,cir-

cuits which include, respectively, the coils of the solenoids 6,2 of the several magnetic elements 37, 59, 60 and 61 of the uppergroup,

and these partial circuits have series .connection with each other as shown at 86 and also'have, connection with. theconductor 55 of the shunt field circuit wherein" the contacts of the circuit. breakin devices of the mag11eticelements37 59 an 60 ofthe upper ductor 55 of I position of the parts-at startingand'before group are normally included, The partial circuit 82f0r the solenoid winding'of-the element 37 is, as above stated, essentially a part of the conductor55 so thatit will be." seen thatv assoon as the controller is actu-x 'ated to close the circuit at the switch-board by manipulation of the lever 43 of'thepilot switch. 42 as, above described, the solenoid of the element 37, which is designedforprimary or nitial controlling operation among 1 the magnetic elements of the upper group,

will be energized, and by raising its core willoperate to break communication between the contacts 56 and 58 of its circuit breaking device.

In Fig. 1, the contactblock 36 of the auxil -iiary switch for controlling the supply of energy to the main switch, actuating mechanism 30 is carried upon the stem 6. of-the solenoid of the magnetic element ,37 and is arranged tooperate in a way similar to the connector 57 to break communication between its contacts 35 and 38 when said stem 63 is moved upward at the energization of said so'lenoid- 39 is a' conductor connectedwith the conductor 34 in parallel with the auxiliary switch formed of contacts35 and Y 38 and block 36 and connectedwith the main esepsa switch contacts 9 which communicate 5 the conductor of the shunt field circuit, through switch element? and contacts -.t,

with the feed terminal 2, and in said parallel parallel .with the circuit-breaking device of conductor 39 is included a resistance 39 of sufiicient capacity by means of which the current from the feed conductor is normally prevented from traversing the conductor 39 and short circniting the auxiliary switch. By this arrangement it will'be seen that when the solenoid of element 37 is energized on the closing of the motor circuits as above described, the block of the auxiliary switch will be raised to break communication bca I tween the contacts 3a and 3h, whereupon the current from l ecd't'crminal 2 will traverse the conductor 33), the res'..taiiee 35! of which will serve to cutdown the si'ipply of energy to the energized solenoid at the switch actuating mechanism 30, so that.onl v sullicieiit energy will be supplied thereto to' permit the energized solenoid to retain the main switch shaft (3 in the position to which it was rocked when the pilot switch lever 43 was first thrown.

that when the pilot switch is lirst nianipu. lated to operate the switch actuating met-liin this way it. will be seen anisin 3t), an ample supply of energy is supplied to said mechanism 30 by way of the auxiliary switch to permit the mechanism to perform the heavier duty imposed upon it, but' as soon as the main switch is operated .and the power required to be exerted at the mechanism 30 fol-retaining the main switch in position is lessened, the element 37 will'act to lift the bloclcZ-iti ot' the auxiliary switch and cut the resistance 39 into circuit with said witch actuating mechanism 30 to reduce the supply of current. thereto.

In Figs. 3 and 3, the arrangement of the auxiliary switch for controlling the supply of energy to the main switch actuating mechanism 30 is illustrated in a modified form, being. embodied as a separate device inst ad oias a part of the lirst. magnetic ele ment 37 in the upper group. As herein shown the auxiliary switch device-37 is formed similarly to one of the elements 59, tit) and 61., except that it is provided with no circuit closing device similar to the brush 75 and contacts 76 and 77, but. carries on the stem of its solenoid (33, as shown iii the detail view Fig. 1-, the block 36 normally bridging the space between contacts 35 and 38, but adapted to-be lifted outof conniiunication therewith on the cnergization of the solenoid G2, the windin r of which, as shown in Figs. 2 and 3 is inc uded in the shunt lield conductor 53 so that said solenoid will be energized to break communication between contacts 2,5 and 38 as soon as the main switch shall have been thrown to close the motor circuits.

Each of the partial circuits 83. 84 and 85 for the elements 59, and 61 of the upper group has a circuit connection-at S7 with tion out of contact with their contact 76 and 77,- whereby the partial circuits 78,

and each of these last-named partial circuits.

is thereby connected in the shunt-field in the preceding magnetic element, the partial circuit 83 for element '9 being connected in parallel with the cireiiit-breaking device of the element 37, the partial circuit 84; for element. (it) being in parallel with the c1rcu1tbreaking device of element 59 and the partial circuits S5 for the element (51 being connected in parallel with the circuit-breaking device oi? the element t30.' Said partial circuits are therefore open to the flow of current through the shunt field, but since each such partial circuit includes a certain re 58. the current will t'avcrse the conductor SS-past each circuit-breaking device to and llll'OllQlll'llO partial circuit 82 and the solenoids of elements 55). tit) and 61 will not; be energized until after the first element 37 shall have operated its circuitbreaking device to interrupt connnuititration between its contacts 56 and 5S.

...\s above stated, the circuitbreaking devices of the magnetic elements of the upper group have their connectors 57, 57, normally in lowered or closed position, while the brushes 75 of the circuit-closing devices for said elements are normally in lowered posipoints 78, are normally open, but it is evident that when the-several magnetic elements are actuated and theirsolenoid cores are elevated, the connectors 57 and brushes 75 will be revcrsely actuated, whereby communication is interrupted between the contact p0ints'56 and 58 of the cirouit-break'ing devices while communication is etiectcd between the contacts 7t and 77 by. engagement of the brushes T5 therewith, so that the partialcircuits 73-, 78, are successively closed for shortcircuiting the several sections 26, 25 and 24' ot the starting resistance, together with the series-field windings 21, as said elements 37, 5t), tit) and (31 of the upper group are successively operated, and since the stems 63 of the solenoid cores of said elements are capable, ias above explained, of a certain extent ofupwardmovement before the connectors 57 are picked up to break communication between contacts 56 and 58, it IS obvious that the brushes 75 will, by such inde- )endent initial movement of the stems 63 be moved into communication with their contacts 76- and 77 before communication is interrupted between contacts 56 and 58 and consequently the operation ofthe magnetic elements in closing the partial circuits 78 and cutting out the sections of the starting belikewise actuated to cut out the series field coils 21' of the motor.

resistance and series field coils 21 is timed and assured before the several circuit breakinghdevices are operated.

When the connector 57 of 'the circuit breaking device for the primary or controlling element of the upper group, on the actuation of said elenientafter closing ofthe motor circuits, is lifted out of communication with itscontacts 56 and 58, the corresponding partial circuit 78 will be closed to short circuit the first section' 26 of the starting resistance, and the flow of current from the shunt field conductor 55 through partial circuit 82 will be interrupted, whereby the next partial circuit 83 parallel with t-he circuit reaking device of the element 37 in the shunt field. circuit and including the solenoid winding for-the next element 59 in the upper group will betraversed by the shunt field currentwhereby said next element 59 will be actuated by the energization of its solenoid and at the same time, by reason of the series connection at 86 between the partial circuits 82 and 83, the solenoid of said first, element will remain ener ized so that ductor 55 and simultaneously with'such in terruption to close the corresponding par-"g tial circuit 7 8 whereby the next succeeding- Section 25 of the starting resistance is cut out of the series field. By this operation of the second element 59 of the upper group, the partial circuit 84-. for the third element 60 and which is in the shunt field circuit parallel with the circuit breaking device. of element 59 is cut into said circuit so that the third element- (50 will be operated in a manner similar to the elements 37 and 59, cutting out the third starting resistance section 24 and cutting the partial circuit 85, parallel with its circuit breaking device and including the solenoid winding of the fourth element 61 of said upper group into the shunt field circuit so that said ffourth element will The magnetic elements 49, 50, 51 and 52 of the lower group are substantially similar to those of he upper group in construction and arrangement except that the circuit closing devices comprising brushes and contacts 76 .and 77' with their appropriate circuit connections are dispensed with, said lower elements being; provided only with the the connection 87 of saidcircuit breakin devices coiiipvrisingjthinnertors 57 control lug-communication between contacts 56 and 58 which are included in the shunt field circuit conductor 55s0 that the;

flow of current through said conductor may 70 be interrupted at various points bythe successive operation of said elements 49, 50, 5'1 and 52 of the lower group. The first element. 49 in said lower group is also, like the first element 37 in the upper group,

lower elements and exerts a controlling-influence upon the remaining elements of said lower group which cannot be operated until j a fter said first element 49 shall have completed so its operation and lifted the connector 57 of its circuit breaking device to interrupt'coii'i-v niunication between the contacts 56 and 58.

The solenoid winding of the prim-a1. element 49 of the lower group'is include :ina '85 partial circuit 47 which is arranged for par,- allel inclusion in the supply circuit forthe solenoids 31 and 31 for the main switch actuating mechanism 30, for which purpose one terminal of'said partial circuit 47 has!!! connection as seen at 48 with the conductor Y 45 leading from the contacts 5 of feed teik minal 8 at the switch-board and the opposite terminal of said partial circuit has common V a similar 55 connection with contacts 46 and 46 to but arranged outside of the above de-' scribed contacts 44 and 44 at the pilot switch so that the lever 43 at said pilot. switch when first moved to establish comma .iiication between contacts 41 and 44 (01 413 and it astlie case may be) to energizethe solenoid at the switch actuating mechanism 30 may be afterward 'f'iirther moved to a second position, as for instance toward the ri in as shown in Fig. 3,

and'46 and the currcnt'for lenoid at mechanism 30 is caused to traverse the partial circuit *7 and to energ ze.

thsolenoid. at the controlling element 49' of {1110 this arrangement it field resistance sect ons for variation ot the running speed of the motor cannot be ef-f fected until after the operator shall have suitably manipulated the pilot switclr lever 43 to close the partial circuit 47. Thus the motor may be started and run at low speed by shifting the lever 43 to its first position wherein the upper elements are allowed 'tio 1 o crate to cut out the starting successively series windings so that the esistance an I motor is permitted to run with full current when desired, the, speed may be increased by further movement 39 in the-shuntfield and adapted for 25 primary or initial actuation among the four v whereuponit esta lishes communication between contacts 4'1- energizingtheelement 49- is' L15 the solenoid winding at element is in the got the pilot switch lever whereby as will be presently explained, the shunt resistance sections49, 50, 51 and 52 are successively inserted in the shunt circuit.

88, 90' and 91 are three partial circuits; somewhat similar to the partial circuits 84 and 85 for the three last elements of the upper group, and these partial circuits 88, 90 and 91 include, respectively, the solenoid windings for the respective elements 50 51 and 52 of the lower group and have series. connection as shown at 92 with each other besides having connection as shown at 93 with the conductor 55 of -tlie shunt field circuit, whereby each such partial circuit 88,

, 90 and 91 is connected in the shunt field parallel with the circuit breaking device, comprising connector 57 and contacts 56 and 58,

of the preceding element, the arrangement being such that the partial circuit including shunt circuit parallel with the circuit breaking device at element 19, the partial circuit I 90 for. element 51 being in parallel with the .25,

circuit breaking device for element 50 and the partial circuit 91 for element. 52 being in parallel with the circuit breaking device for element 51. These several partial circuits 88, 90 and 91 for the elements 50, 51 and 52 ofithe lower group include the respective sections 1-9, 50 and 51 of the shunt field --resistance and their resistance is therefore .sufiic ently high to insure the flow of the a current along conductor by way of connectors 57 of the circuit breaking devices when these parts are in their normal lowered position, so that. normally, the solenoids of the elements of the lower group will be deenergized so long as switch lever 43 is not.

tial circuit 88 including the first section 49 of the shunt field resistance together with the solenoid vinding at the next succeeding element 50 which will thereupon be energized and in its turn will serve to again interrupt the shunt field circuit at its circuit breaking device whereby the corresponding parallel partial circuit 90 including the next section 50 of the shunt field resistance together with the coil of the solenoid at clement 51-will be traversed by. the shunt field current, energizing element 51 to operate its circuit breaking device so that the shunt field current will be causedto traverse the parallel partial circuit 91 inchiding the next section :31 of the shunt field resistance toceases gether with the solenoid-winding at the'last element- 52 of the lower group, so that this last element will also beenergized and'operated to break communication between. the.

contacts 56 and 58 of its circuit breaking device. The series connectionsof these partial circuits with each other as seen at 92 are beyond the resistance sections of the sevcral partial circuits, so that when the circuit breaking devices are successively operated as above described, the said resistance sections will be connected in series in the shuntfield circuit. The-final section 52 of the shunt field resistance is included in a partial cir-1 cause the shunt fieldcurrent. to traverse said partial c1rcu1t'94 lncluding the last resistance section which is thereby also inserted in the shunt field 1n series with the first three sec' tions 19 50 and 51.

By the construction above described it will be apparent that the elements of each group are under independent control of the operator at the switch lever 43, he elements of the first group being controlled by the initial inovcn'ient of the pilot switch lever to contacts (it or it, while those of the lower group are. under control by the further movement of said lever to contacts 16 or 46, but. it will also be apparent that when said lever has been moved to either of its two positions, there is no further control of the operator as concerns the operation of the individual elements of either group. In this way when said pilot switch lever has been moved to one of its first positions as shown in Fig.

2 and the primary element, 37 otthe upper group is operated, control of the next element of said upper group passes to said primary element 37 and so on with each elementof the group so thateach element in that group is controlled by the preceding element. "1 he same is true ot the elements of the lower group after the primary element 49 thereof has been energized by movement of the: pilot switch lever'43 to one 'of its second positions as shown. in Fig. 3, and

-in this way precaution is afforded against damage to the parts from too rapid 'inscrtion or cutting out of the shunt and series.

resistance sections, since the retarding device of each element will afford a sufficient intervalbetweeneach two successive resistance variations to prevent such damage.

By the arrangement above described, were the pilot switch lever 43 moved from its central position past its first. contacts 44 or 44 and into engagement with its second contact 16 or 46, it is evident that substantially simultaneous operationof the primiiry ele; ments 37 and 49 of the respective upperand lower groups would occur, whereby the remaining elements in each group would be operated in uiison so that the insertion of the shunt field resistance sections would be substantially simultaneous with: the cutting out of the corresponding starting resistance sections, and to prevent such defective opera-- cuit has connection at 530 tion -I provide 1neansfor controlling the operation of the elc'inentslof the lower group from those of the upper. 'Ihis means comprisesa partial circuit 8 ,hone' terminal of which has connection with the shunt field? conductorfi s'r at a point bet-ween the circuit breaking devices of the element 61, and 49 in the respective upper and lower groups, while the other terminal of said partial C11- Q5 with the partial circuit 88 which provided for actuating the element of the lowergroup. This i partial circuits!) being-thus in serieswith conductor and traverse the partial cir its 88 and 89 from 1 shown at Fig. 3, the Sllllgt field current willv the point of-connection 3 of partialcii'cu'it 88 with shunt field conductor-'55 at element 50 to thepoint of connection of partial circuit 89 withshunt field conductor 55, the connector57 at element 61- being in lowered positionqsince the preceding elements inthe 'rst group will not have had tune to operate to energize saidelelnent and break said partial circuit 89,. In this way,.-neither of the shunt resistance sections is inserted: until after communication-has been. broken by way of the partial circuit 8%),but when the elements of the, upper roup. have finished operation, and the'la'st element 61 has raised its core and operated its circuit breaking device to interrupt'the partialcircuitSQ, that portion of the partial circuit 88 which is cuit '89 and includes the parallel in the shunt field with partial. cirsolenoid winding of element 50 together with the. first section 49 of the shunt field resistance will be traversed bythe shlmt field current, said resistance section being thereby inserted in' the shuntfield to increase the running speed .a-ndtheelen ent 50 being energizedto operate Its circu t breaking partial circuit 90 1110111 1 device, so that the ng the solenoid coil of element 51 and. the second section 50 of the. slmntjresistance will be traversedby the -shunt field. current, said element-'o-lflheing.

therebyenergized in itsv turn to 'operatej'its circuitbreaking device andin'sertLthe neXtT 6 5' partial circnit -.9l' including the solenoid windin at element 52 and thethird section 51 of tie shunt resistance in the shunt circuit and the element. 52 being thereby energized to operate its circuit breaking device whereby the fourth section of resistance 52*" is inserted in the shunt circuit. This opera: tion-ab'ove described can, however, only take placewhenltlle'pilot switch lever has been saidelement 1s; 1 iiot ener ized, its lowered connector 57 will bridge tie contacts 56 and 58 and afi'ordna short circuit by means of moved to energisenelement 49, since when which the shunt field current'is prevented from flowing-through partial circuits 88 and 89 by reason. of the greater resistance in said partial circuits, but after the elements ,49 and 61 have been operated as above described, the partial clrcuit. 88 is. free to be traversed'by the current ofthe shuntfield.

By' my improvements it will be seen that across tie individual solenoids is very. low- ,I do'not require to use such large windings in the solenoids oi to form said windings from such fine, gages of wire as is necessary in other constructions, and the small dificrencevof'potcntialbetween the solenoid wi nd-, 'IINTS litible to result in damage to the insulation andconsequent break down of the controller.

By reason of the loose or compensating connectiona t 29 between the shaft 12-01 the, reversing switch and the main switch shaft 6 which permits the arms 11 and 11- ofthc reversing switch to maintain communication with. their respective contacts even after the supply-circuit has been interrupted by the return of the main switch shaft to its central or intermediate position as above described, the shuntfield connections a'remaintained with'the armature and-current flows in the sojjhat' thesol'enoidftill or 31. of switch actuof ener y is efiected and as the potential v v.

the ma'gthe several elements, excepting the controland other parts of the circuit is not so in Fig 1 or ofvthe solenoid 7 at 379m. thefcon'structlon shown in. Fig, 3,

ating mechanism 30 cannot be again .ener gized to reverse .the armature connections atthe reversing switch. until the motor comes to rest, the block 36 remaining in raised position until the corresponding solenoid has been denergized. Thus after once starting, it is impossible to reverse or again start until the motor shall have come to rest; This is a great advantage, especially, wherethe motor is started under load and has a brake for stopping,.as for. instance on motors for electric elevators. It is so easy to operate the main switchfrom the pilot switch thata careless or irre's'pons'ble operator -might damage the main switch by throwing. it back continuously and uselessly.."

From the above description it will be obvious that the improved controller constructed according to my invention is of a comparatively sim 1e and inexpensive nature and is especia ly well adapted for use by reason of the economy afforded by it in the consumption of energy and also by reason of the ease and convenience with which the device may be operated and of the precaution afiorded by its use against damage due to carelessness ,or inattention on the art otthetoperator and it willalso be obvious fi'iiin the above description that the device is susceptible of some modification without material departurefrom the principles and spirit of the inventiona-nd for this reason I do not desire to be understood as limiting myself to the precise form and arrangement of the several parts herein shownin carrying out my invention in practice. For ex ample, if desired, means may the pilot switch for controll ng the'insertion of the successive shunt resistance sections, so that the motormay-be run at intermediate speeds as well as'at the high and low speeds afforded by Or if desired, the main switch may be manuall actuated instead of electrically actuate as herein shown. Where the main switch is manually actuated, the element 49 may be dispensed with and mechanicalmeans maybe provided for controllingthe com- 50- of said element, for aifording the necessary speed variations.

While I have ma wit the shunt-field of the motorfit is evident that this ,is not an essential feature of: the invention, since said elements or.solenoids may, with good results, be connected in other shunt circuits as, for example, cuits of the large magnets or solenoids '30 and 31, or in circuit with abrake-magnet where the invention is tion with a motor equipped withelectr'ic brakes. While it is advantageous and pref- 6 erable, from the stand-point of economy, to

herein shown the several and forth, using the heavy-starting currents be provided at the construction herein sh0wn..

munication between the contacts 56 and 5 8 etic elements or solenoids in circuit' the cir f employed in connecseveral circuits;

in thc shunt-field, it inust be borne in-mind .that the required resistance variations may .1.

be accurately and uniformly attained in 'the- Having thus described my invention,1\\'fha t Ifclaim and desire to-s'ecu're by Letters 1 tllT-- ent is' 7 netic means for controlling the. circuit con-- nections of said starting resistance, and a. magnetic device arranged to. actuate the cir- Q cuit controlling means of the starting resistance and having connections for include 'ing'it in the'shunt field circuit of a motor to 85: be controlled,

tions having circuit connections, contact. devices controlling the circuit connections of v the respective resistance sections, and a plu- 90. rality of magnetic devices each of which has I means for connecting it in circuit with a mo.-' tor to be controlled and controls the circuit connections of another such device with 'a-- "circuit of the motor to be controlled, said ate the contact devices for the several resistance sections; 3. A controller comprising resistance sections having circuit connecti0ns, normally open partial circuits connected in parallel with the respective resistance sections and means for closing t he respective partial circuits and each including a magnetic device liavingcircuit connections for including it in a circuit of the motor to be controlled, and including contact devices actuated from a similar magnetic device. 1 i 4. A controller comprising resistance sections having circuit connections, magnetic devices insertible in a-circuit of the. motor to be controlled and controlling the circuit connections .ofthe respective resistance sections and a plurality of retarding means, one for each of said magnetic devices,-t'or timingthe'operation thereof. v 5. The combinationof'axmotor,'- a plural.-. ity of resistance sections adapted to beiileluded incircuit with the motor and a plu- J rality of interdependent; magnetic devices, 'controlling 'the circuit *connections-joithe respective- 'resistance sections and: .having..,.; means for 'including-them in'circuit. with the motor.

6. The combinationof a-motor,' 'a plural-. 'ity of resistance sections adapted to be includedin circuit with the motor, circuit-. closing devices controlling the circuit conne'ctions of the respective resistance sections. a plurality of magnetic devices havingw" connectfisaid. magnetic clemeuts' or solenoids that a "prime essential 'is to secure thcop; eration ofthe "several magnetic elements 1.1).

. ont roller comprising a starting;1'e-.- slstance having circuit connections, mag-v I 2. A controller comprising resistance secs 1, devices being arranged to successively actu-i nections for the motor, "connected in parallel with the respective re means for including it in circuit with the inotor'each arranged to operate one of the respective Circuitwlosing devices, and other circuit controlling devices each controlled by one of, and controlling another-of said mag:

netic devices. a Y

7, The combination of a motor, a plurality of resistance sections having circult connormally' open partial circuits 1 sistance sections, meansfor closing the respect-ive normally open partial circuits, each such means including a magnetic device ha ing means for including it in circuit; with the motor, and circuit controlling devices eachfcont-rolled by one of, and controlling another of the said magnetic devices.-

8. ..l-he combination of. a motor, a 'plurality of resistance sections having circuit connections with the'inotoi', andinterdependcnt magnetic. elements each actuated from the i flow of currenti'n a circuityof said motor and arranged for successive operation to control= the inclusion of the respective resistance 'sectionsin circuit with the .motor.

9. The-combination of. a motor, a plurality' of resistance sectionsadapted to be in cluded in circuit'vviththe motor, aplurality- '"ling the circu t connections of the respective of interdependent magnetic devices 'control- I'BSlStflIlCG sections and having means for ineluding it in circuit. with the'inotor, and a plurality of retarding means, one for each oi :su'ch magnetic devices, for timing the operation thereof. i

10.'The combination of; a compoundwound motor, a resistance adapted for insertion in the series-field circuit thereof, magnetic-means for short-circuitingsaid resistance, other magnetic means for short-circuitmg the series-,\v1ndings of the motor and "electrically actuated means comprising con tact devices controlling the, circuit connecof the motor to- 11; The combination of a compound spective l resistance the motor, 55.v

iranged to Ying, devices. z 12. The coi'nbination of ,a compound- .sertible in a motor circuit from the flow of current in a shunt-circuit.

tions of each such short-circuiting means and adapted to be included in a shunt-winding be controlled.

'- jvonnd motor, 'a' sectional resistance "in cir ,(ZllltJVlth the series-windings thereofl'a plurality ofdevices for short-circuiting -the resections, another device forshorbcircuiting theseries-windings of and interdependent magnetic de, vicesinsertible in a-motor circuit and arvvound motor, a plurality of resistance sec tions adapted] forv insertion in' the seriesfield circuit thereof, magnetic elements in and each actuatedflii'nd arranged for successive operation to con- ,itrol the circuit connections of the respective including them in circuit with resistance sections and of the series-windingsof'the motor, and circuit-closing devices each controlled by one of the magnetic ele, ments and controlling another of said magnetic elements.

sistance having circuit connections for coni 13. A controller comprising a sectional i-enecting 'it in a motor 'circuit and having normally closed short-circuiting connections, means capable of operation to successively hreak'said short-circuiting connections-and a 'magnetic device controlling said" circuitbreaking means and adaptedfto be included in a shunt-circuit.

'14. A controller comprising resistanci necting them in circuit'ivithui motor to be controlled, short-cnrcuit-mg connections tor vices controlling the short-circiii'tiug connections of the respective resistance sections, and interdepemlent magnetic trolling said contact devices and adapted to controlled. v V 15. The combinatlonoi' a motor having a means for coni'iectioi'is in the shunt field ircuit, one such conductor including a resistance and a magnetic element controlling the -fi0w of current in are shunt' field circuit along said paralll conductors and actuated actuate each of said short-circuitfi'om the How of current in the shunt field circuit of the motor.

- 16. The combination ot a motor having a rent flowing in the shunt for controlling the flow shunt field through each field circuit, means of current in the of the i-" operate each of said controlling means and included in the shunt field circuit.

1.7. T e, combination of a-motor having a "sections adapted to be traversei'l by-the current flowing in said circuit and-a plurality of magnetic devices each controlling the flow ofcurrent in the shunt field through one of said resistance sections and each included in the shunt field circuit. 18. The combination ofa'motor, having a means to vincludetlieni'incircnit with the motor, a the How of'current ma motor circuit-through being controlled bythe flow of current in the. shunt field circuit o f'themotor andtheoperation of each succeeding element riesloeing controlled by preceding element. I i

i shunt fieldcircuit, resistance sections lravthe respective resistance sections, contact dcdevices conbe included in circuit with the motor to he shunt field circuit, parallel conductorshaving shunt field circuit, a plurality of resistance sections adapted, to be traversed by the cursistancesections and a magnetic device arrangedto shunt field circuit, a plurality of resistance series of elements'each controlling I 19. The combination off a motor having a 1 2 sections having circuit connections for conthe motor, a series of elements each controlling the flowot current in a motor circuit to include them in circuit with through one ofthe respective resistance sections, the operation of the first element in the seriesheing controlled by the. flow of current in the shunt fiel'd circuit of the motor and the operation of each succeeding element in the series being controlled by the operation of the preceding element and means tor retarding the operation of each of said elements.

-zlh'lh'e combination of a motor having a shunt field circuit, resistance sections having means to include them in circuit with the'motor, a series of tlellltHlS havingcircuit connections to actuate them from the current flow in the shunt field circuit of the mo-' tor and each controlling the How of current in a motor circuit through one-of said resistance'sections, means for controlling the How of current in the shunt field through the circuit connections of the first element of the series and means, controlled by the operation of a precedin element in the series for controlling the fiow of current from the shunt field through the circuit connections of each succeeding element in the series. i

:31; The combination of a motor having a shunt field circuit, two resistances having means for including them in circuit with the motor, elements havin circuit connections for actuating them from the current How in the shunt field circuit of the motor and each controlling the flow of current in a motor circuit through one of said resistances, means actuated from the operation of one element for controlling the current flow in the shunt field circuit through the air aiit connections of the other element and other means for controlling the ope 'ation of said elements independently 'oi'each other.

resistances, means '12. The combination of shunt ficld circuit, two sectional resistances ha ring means for including them in different motor circuits, two groups of elements, the elements of each group controlling the current flow in different motor circuits through the respective sections of one of said for controlling the operation of the elements ofone group from the operation of the elements of the other group and other means for controlling the opera tion of the'elements of each group independently of the other group.

23. The combination of a motor having a shunt field circuit, two sectional resistances having means for including them in (litterent motor circuits, two groups of elements, the elements of the respective groups controlling the current tiow in different motor circuits through the several sections of the respective resistances. means for controlling the operation of'the first element in one a motor having a circuits and controlling the resistance in circuit With group from the current flow inthe shunt field circuit'ot the motor, means for controlling the ope 'ation of each succeeding element in that group from the operation of the preceding element in that clip and means for controlling the operatlon of the elements of the other group independently of said first-named group.

24. The combination of suppl terminals, a motor, a switch device controlling. connection of the motor circuits with the suppl terminals, solenoids for actuating the switc device to make connection between the ter-' minals ofthe motor circuits and said supply terminals and magnetic meansincluded in a shunt-circuit and controlling the operation of said solenoids.

25. The combination of Suppl terminals, a motor. a switch device control ing connection of the motor circuits with the supply terminals, electrically operated -mechan1sm having circuit connections and arran ed for actuating the switch device to ma e and break connection between the terminals of the motor circuits and said supply terminals, a resistance having means for including it in the circuit of said electrically operated mechanism and 'magnetic means actuated from the fiowof current insertion of said said electrically operated mechanism.

26. The combination of supply terminals, a motor, switch mechanism controlling the connection of the motor circuits with said supply terminals, electrically-operated switch-actuating means comprising a partial circuit adapted for connection across the supply terminals, and means controlled. from the flow of current in a motor circuit for varying the current fiow in said partial circuit of the switch-actuatingmeans.

27. The combination 0 supply terminals, a motor. switch mechanism controlling the connection of the motor circuits with said supply terminals, electrically operated s\vitch-actuating means comprlsmg a partial circuit adapted for connection across the supply terminals, aresistance insertible 1n said partial circuit. and ineans controlledin one of the'motor a motor. switch mechanism controlling the connection ot iheii'iotor rcuits with said supply terminals. electrically-' "-,op erated switch-actnating means comprising a partia circuit adapted for copnection, across the supply terminals. and rfieans controlled from the actuation of the switch mechanism and controlling the supply of cu'rrent to said partial circuit of the switch-actuating means.

29. The combination of supply terminals,-

a motor, switch mechanism controlling the connection of the motor circints with said supply terminals, electrlcally operated switch actuatin m ans comprising a partial each controlled from the operation of one. of 7 said magnetic devices and controlling the circuit connections of another such magnetic device with a; motor to he controlled.

31.,A controller comprisin a series of magnetic circuit controlling (fevi ces having means for including them in circuit with a motor to be controlled, each such device ha ving retarding means aml being provided with contact devices whereby near the end of its stroke it energizes the succeeding magnetic device in the said series.

32. A controller comprising magnetic circnit-controlling elements arranged in two series, the elements of each series being adapted for successive operation, means the elements in one series for controlling the' adapted for operationin unison with one of operation of the elements of the other series,

and mechanism for independently-control- 5 ling the operation of the elements of the respective series.

A controller com )rising a series of magnetic circuit-controlling devices, and means, for including them in circuit with a motor or translator to be controlled, each such device having retarding means and being provided with contact devices \vl'iereby near the end of its stroke it energizes the succeeding magnetic device in the said series.

Signed at Cincinnati, Ohio, this 13th day of January, 1906.

OSCAR 'F. SHEPARD, J-n. -\\'it-nesses:

' .JOIIN ELIAS JoNns,

L.,W JONES. 

